Exploration of the static softening behavior and dislocation density evolution of TA15 titanium alloy during double-pass hot compression deformation

作者：Ma, Qing; Wei, Ke^*; Xu, Yong^*; Zhao, Lijuan; Zhang, Xiang

来源：Journal of Materials Research and Technology-JMR&T, 2022, 18: 872-881.

DOI：10.1016/j.jmrt.2022.02.122

• TA15 titanium alloy
• Microstructure evolution
• Static softening behavior
• Dislocation density

The static softening behavior and dislocation density evolution of TA15 titanium alloy during double-pass hot deformation were investigated under the deformation temperatures (910 degrees C-970 degrees C) and holding time (0s-2200s). The microstructure evolution of primary a phase was observed by optical micrograph (OM), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The evolution of dislocation density was investigated via X-ray diffraction (XRD) and W-H model. The results showed that the globularization behavior of primary a phase is emerged during the inter-pass of double-pass hot deformation. The globularization process is promoted by the extension of the inter-pass holding time and the increase of the deformation temperature. The groove of primary a phase is preferentially generated when the inter-pass holding time within 1000s. Subsequently, that groove of primary a phase is separated and then those a phases are dissolved when the holding time over 1000s, leading to the fraction of a phase reduction. Compared with deformation temperature of 910 degrees C and 940 degrees C, all of the primary a phases are completely separated after 1000s of the inter-pass holding time under 970 degrees C. Additionally, through the analysis of various crystal surface of a phase, the dislocation density in the inter-pass gradually decreases with the holding time and deformation temperature increasing.

• 单位
  南昌航空大学; y